Although reliable rechargeable batteries represent a key transformative technology for electric vehicles, portable electronics, and renewable energy, there are few nondestructive diagnostic techniques compatible with realistic commercial cell enclosures. Many battery failures result from the loss or chemical degradation of electrolyte. In this work, we present measurements through battery enclosures that allow quantification of electrolyte amount and composition. The study employs instrumentation and techniques developed in the context of zero-to-ultralow-field nuclear magnetic resonance (ZULF NMR), with optical atomic magnetometers as the detection elements. In contrast to conventional NMR methodology, which suffers from skin-depth limitations, the reduced resonance frequencies in ZULF NMR make battery housing and electrodes transparent to the electromagnetic fields involved. As demonstrated here through simulation and experiment, both the solvent and lithium-salt components of the electrolyte (LiPF6) signature could be quantified using our techniques. Further, we show that the apparatus is compatible with measurement of pouch-cell batteries.

中文翻译：

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能够对具有超低场核磁共振的电池中的电解质成分进行无损观察


尽管可靠的可充电电池是电动汽车、便携式电子产品和可再生能源的关键变革性技术，但很少有与逼真的商用电池外壳兼容的无损诊断技术。许多电池故障是由于电解液的损失或化学降解造成的。在这项工作中，我们通过电池外壳进行测量，允许量化电解液的数量和成分。该研究采用了在零到超低场核磁共振 （ZULF NMR） 背景下开发的仪器和技术，以光学原子磁力计作为检测元件。与受集肤深度限制的传统 NMR 方法相比，ZULF NMR 中降低的共振频率使电池外壳和电极对所涉及的电磁场透明。正如这里通过模拟和实验所证明的那样，电解质 （LiPF6） 特征的溶剂和锂盐成分都可以使用我们的技术进行量化。此外，我们表明该设备与软包电池的测量兼容。